This invention relates to the destruction of underwater objects, and, more particularly, to their destruction using a targeting system and gun system located above the water.
In wartime, underwater mines are commonly encountered at invasion beaches and harbor entrances or in shipping lanes. The mines are placed at relatively shallow depths below the water in these locations to destroy ships or at least impede progress by requiring extensive operations to detect and remove the mines. The mines are designed to detect the presence of a ship and to detonate as the ship passes or contacts the mine.
A number of techniques are used to locate underwater mines. Once located, the mines can be avoided or destroyed. In some cases, it may be feasible to temporarily continue operations while avoiding but not destroying the mines. Avoiding densely arranged fields of mines during continuing operations is difficult and time consuming, and therefore mines are usually first located and then, either immediately or sometime thereafter, destroyed.
Several techniques are used to destroy mines. In one, a decoy simulating the signature of a ship is towed by a helicopter or a mine-sweeping vessel over a mine field in an attempt to cause the mine to detonate responsive to the presence of the towed decoy. This technique operates under the assumption that the detonating sensor and discrimination algorithm of the mine can be fooled by the decoy. The microcircuitry of the underwater mine can be programmed with various countermeasures that render this technique somewhat unreliable in practice.
In another approach, the underwater mine is detected by magnetic mapping, sonar sweeps, or other technique. Swimmers or robot vehicles in the water place explosive charges in the vicinity of the mine, and the charges are detonated to destroy the mine or otherwise render it ineffective. This technique is slow and expensive and is also hazardous when swimmers are used.
There is a need for an improved approach to neutralizing the effects of underwater mines. Such an approach should be highly effective, safe in the sense that lives are not endangered in the process of removing the effect of the mine, and as fast and economical as possible. The present invention fulfills this need and further provides related advantages.